Universal joints

ABSTRACT

In a plunging constant velocity universal joint the inner member is formed with a bore containing bearing means having bearing surfaces centered on the joint center, a location member is contained in the bore and has a part-spherical outer surface engaging the bearing means. Resilient means or travel limiting means act between the location member and the outer member of the joint.

United States Patent Shirley et al. 1451 July 25, 1972 [s41 UNIVERSALJOINTS [56] Relerences Cited [72] inventors: Brian William Shirley;Philip i'lutehlnson, UNITED STATES PATENTS Englmd 2,617,279 11/1952Miller, Jr. ..64/9 x 73 Assign; mrfldd Tnmwons n 3,540,232 I l/l970Breuer ..64/2l X Birmingham England 2,968,936 "i961 CIO'SC 3,162,024l2/l964 Breuer et a]. ..64/21 x [221 d= 1970 3,310,961 3/l967 Ristau..64 21 App! Primary Examiner--Kenneth W. Sprague Attorney-Spencer &Kaye 30 Forei A icatlo Priorit Date I l W n y 1571 ABSTRACT Nov. 20,I969 Great Britain ..56,739/69 in a plunging constant velocity universal101m the Inner member is formed with a bore containing bearing meanshav- 52 us. (:1 ..64/7, 64/2l s bearing surfaces wnered 1 cemflalocation [51] 3/20 member is contained in the bore and has apart-spherical outer [58] Field olSearch ..64/7 9 9 A 21 surface beamsmeans Raine means limiting means act between the location member and theouter member of the joint.

8 Claims, 5 Drawing Figures I '1 l J. y I wi Q; as

N"- Z i Patented July 25, 1972 3,678,706

2 Sheets-Sheet 1 UNIVERSAL JOINTS BACKGROUND OF THE INVENTION 1. Fieldof the Invention This invention relates to universal joints of theconstant velocity type which are capable of accommodating relative axialmovement between the driving and driven members of the joint. Suchjoints are hereinafier referred to as plunging C.V. joints.

In a transmission assembly which includes a plunging C.V. joint at eachend of a shaft, it may be necessary to damp or to limit axial movementsof the shaft, particularly when the shaft and joints are of largedimensions as would be used in, for example, transmissions forlocomotives and heavy engineering applications.

2. Description of the Prior Art Previous proposals to achieve damping ofthe axial movements of the shaft have included blocks of elastomericmaterial acting on the ends of the shaft or have included a springacting between the driving and driven members ofeach joint.

The blocks of elastomeric material which have been used have not beencapable of progressive damping over the whole range of relative axialmovements and the springs have been positioned such that, onarticulation of the joints, the springs have been subject to frequentdistortion and buckling thus reducing their fatigue life.

It is accordingly an object of the invention to provide an improvedplunging C.V. joint which includes damping spring means acting along thejoint axis irrespective of joint angulation thereby avoiding thepossibility of spring failure due to continual distortion or buckling inoperation.

A number of proposals have been made for limiting axial movements ofaplunging C.V. joint but it is a further object of the invention toprovide a limited travel plunging C.V. joint formed from components usedto produce a damped plunging C.V. joint.

SUMMARY OF THE INVENTION The inner member of a plunging C.V. joint isformed with a bore containing bearing means having internalpart-spherical surface means the center of curvature of which coincideswith the joint center. A location member is contained in said bore andhas a part-spherical outer surface complementary to that of the internalsurface means of said bearing means. Resilient means or travel limitingmeans act between the location member and the outer member of thejoint.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawing:

FIG. I is a sectional view of a plunging C.V. joint which includesdamping means operative during relative axial movements between theinner and outerjoint members,

FIG. 2 is a sectional view of part of a plunging C.V. joint showing amodified form of damping means,

FIG. 3 is a further sectional view of part of a plunging C.V. jointshowing a further modified form of damping means,

FIG. 4 is a sectional view of part of a plunging C.V. joint whichincludes damping means as shown in FIG. 1 and, in addition, is providedwith a forced lubrication system and,

FIG. 5 is a somewhat diagrammatic representation of a pair of plungingC.V. joints provided one at either end of a torquetransmitting shaft.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The joint shown in FIG. 1includes a hollow outer member [0 which has a cylindrical bore formedwith a series of angularly spaced longitudinally extending grooves 11.An inner member 12 is provided within the outer member and the innermember 12 has a part-spherical outer surface which is formed with acorresponding number of straight grooves 13 which co-operate with thegrooves II to provide ball tracks along which balls l4 move during bothjoint articulation and plunge. A ball cage 15 with apertures 16 in whichthe balls [4 are closely received is positioned between the inner member12 and the outer member 10. The cage has an inner partspherical surface17 and an outer part-spherical surface portion 18, the surface 17 matingwith the complementary outer surface of the inner member 12 and thesurface portion 18 engaging the cylindrical bore of the outer member l0.

The construction of the grooves II and I3 and the construction of thecage 15 is as fully described in U.S. Pat. specification No. 3,464,232.

The inner member 12 is formed integrally with a shaft I9 which extendsbetween the joint shown in FIG. I and an identical joint provided at theother end of the shaft.

The inner member 12 is formed with a bore 20 which includes a firstportion 21 which opens onto an end face 22 of the inner member 12 and aninner portion 22 which is of reduced cross-section compared with portion2! and portion 22 is followed by a further portion 23 which is ofreduced cross-section compared with portion 22.

A pair of bearing elements 24 and 25 are located within the first boreportion 21, bearing element 24 being located in engagement with ashoulder 26 provided by the junction between the first and second boreportions 21 and 22 and the bearing element 25 is located by engagementwith a clip 27 received in an annular groove in the wall of bore portion21.

The two bearing elements 24 and 25 have part-spherical bearing surfaceswhich are of the same radius of curvature and have the same center ofcurvature 28. The two bearing elements 24 and 25 engage the outerpart-spherical surface of a location member 29, the center of curvatureof the part-spherical surface of said location member 29 beingconstituted by the point 28.

The location member 29 is formed with a throughbore 30 which includes amouth portion 31 followed by an intermediate portion 32 which is ofreduced cross-section compared with the mouth portion 31 and a terminalportion 33 which is of reduced cross-section compared with theintermediate portion 32. The location member 29 is mounted on a fixedguide element 34 which is of cylindrical cross-section and is a closesliding fit in the terminal portion 33 of the bore 30. The fixed guideelement 34 is provided with a head portion 35 which has a part-sphericalpresented surface 36, the head portion 35 being arranged for movementwithin the mouth portion 31 of the bore 30 and the extent of movement ofthe location member 29 relative to the fixed guide element 34 is limitedby engagement of the head portion 35 with shoulder 37 provided at thejunction between the mouth portion 3! and the intermediate portion 32 ofthe bore 30.

A helical compression spring 38 surrounds the fixed guide element 34 andis arranged to act between the head portion of the gude element 34 and ashoulder 39 provided at the junction between the intermediate portion 32and the terminal portion 33 of the bore 30.

The guide element 34 is fixed to an end wall 40 of the outer member 10by a fastener arrangement 41 so that the fixed guide element 34 isco-axial with the cylindrical bore of the outer member 10 and the spring38 acting between the location member 29 and the fixed guide element 34serves to damp relative axial movements between the outer member 10 andthe inner member 12, the location member 29 being fixed against axialmovements relative to the inner member 12 by virtue of its engagementwith the part-spherical surfaces of the bearing elements 24 and 25.

A clip 42 is positioned in an annular groove in the second bore portion22 of the bore 20 in the inner member 12 and the clip 42 acts as a stopfor the head portion 43 of a spring-loaded element 44 which ispositioned in the bore portions 22 and 23 of the bore 20 in the innermember 12 and which is urged by a helical spring 45 towards the stopafforded by the clip 42 for engagement with the head portion 35. of thefixed guide element 34. Member 44 includes a shaft 46 which, at its endremote from the head portion 43, fits within the bore of a bush locatedwithin the portion 23 of the bore 20 in the inner member 12. The shaft46 has its longitudinal axis coincident with the central axis of theinner member I2, said central axis being arranged to pass through thecenter of curvature 28 of the location member 29 and the part-sphericalbearing surfaces of the bearing elements 24 and 25.

In use, when relative axial movement takes place between the outermember and the inner member I2 such that, as viewed in FIG. I, the outermember 10 effectively moves to the left of said figure, the head portion35 of the fixed guide element 34 will engage the head portion 43 of thespringloaded element 44 to move element 44 inwardly of the bore portion22 against the action of the spring 45, the range of such spring-loadedmovement being limited by engagement of the head portion 43 with ashoulder 48 provided at the junction between the bore portions 22 and 23of the bore 20. The range of movement of the location member 29 relativeto the fixed guide element 34 is limited by engagement between the endface 49 of the location member 29 with an end face 50 of one of thefasteners of the fastener assembly 41.

When the relative axial movement which takes place is such that theouter member 10 effectively moves to the right as viewed in FIG. I, thehead portion 35 of the fixed guide element 34 will move inwardly of themouth portion 3I of the bore 30, the extent of relative movement of thehead portion 35 inwardly of the mouth portion 3! being limited byengagement of the head portion with the shoulder 37.

It is to be understood that, when relative axial movement takes placebetween the inner and outer members of the joint shown in FIG. 1,relative axial movement in the opposite direction will be taking placebetween the inner and outer members at the other end of the shaft 19,i.e. ifthe direction of relative movement is such that the inner member12 of the joint shown in FIG. 1 moves towards the end wall 40 of theouter member II], the inner member I2 of the joint at the other end ofthe shaft I9 will move away from the end wall of its associated outermember.

The springs 38 and 45 provide biassing means serving not only to biasthe shaft I9 into a position in which it is central relative to theouter members II] of the two joints but also providing damping meansrestraining the shaft l9 against axial movements.

The joint shown in FIG. I which includes a pair of springs is intendedto be used when large amounts of plunge are likely to be encountered,e.g. where one spring would not have the capacity to control over such alarge plunge. The joint is urged by the springs to its mid-plungeposition.

The joint arrangement shown in FIG. 2 is similar to that that is shownin FIG. I, differing therefrom by the omission of the spring 45 actingon the element 44 of the joint of FIG. I. The head 5! of the joint shownin FIG. 2 is of plate-like form as compared with the part-spherical formof the head portion 35 of the fixed guide element of FIG. 1. Otherwisethe parts of the joint of FIG. 2 are the same as those of the jointshown in FIG. I and are indicated with corresponding reference numeralswith the addition of the sufi'ix a.

The joint arrangement shown in FIG. 3 is similar to that shown in FIG. 2but differs therefrom as to the part between which the springsurrounding the fixed guide element acts. Those parts of the joint shownin FIG. 3 which are identical to the parts shown in FIG. 2 are indicatedby like reference numerals with the addition of the suffix b. The jointshown in FIG. 3 has the spring 38b thereof acting between the end face50b of the fastener arrangement 41b and between an abutment 52constituted by a shoulder at thejunction between the main portion 32b ofthe bore 30b and a reduced cross-section portion 53 of said bore.

The modes of operation of the joints shown in FIGS. 2 and 3 arebasically as per that described above in relation to FIG. 1. The innermember of the joint of FIG. 2 is urged to one end of its travel whereasthe inner member of the joint of FIG. 3 is urged to the other end of itstravel.

The joint shown in FIG. 4 is basically as per that shown in FIG. 1modified so as to provide a forced lubrication system.

The joint shown in FIG. 4 includes those parts shown in FIG. I with theaddition of lubricant passageways. The parts of the joint shown in FIG.4 corresponding to the parts of the joint shown in FIG. I are indicatedby like reference numerals with the addition of the suffix c and it isto be noted that, as shown in FIG. 4, relative movement has taken placebetween the inner and outer members of the joint so that the jointmembers are displaced relative to each other from the positions as shownin FIG. 1, the inner and outer members being shown with their axiscoincident with the inner member having moved to the right as viewed inFIG. 4 relative to the outer member.

As shown in FIG. 4 the fixed guide element 34c is formed with apassageway 54 which is connected to a lubricant reservoir (not shown).

At its end remote from the reservoir, the passageway 54 communicateswith a series of radially extending ducts 55 formed in the fixed guideelement 34c and the ducts 55 permit the flow of lubricant from thepassageway 54 into the bore 30c of the location member 20c. The locationmember 29c is formed with a series of radially extending ducts 56, therebeing one duct 56 corresponding to each of the balls 14c and the ducts56 permit the passage of lubricant into the annular space 57 between thetwo bearing elements 240 and 25c. The inner member is formed with aseries of radial passages 58 communicating with the annular space 57 forthe flow oflubricant into the ball grooves for the flow of lubricantinto said grooves.

The head portion 43c of the spring-loaded element 440 is formed with aseries of circumferentially spaced slots 59 for the flow of lubricantfrom one side of said head portion 43: to the other. The shaft 460 ofthe element 44c is formed with an axial bore 60 which, near its endadjacent the head portion 430, is formed with radial ducts 61 permittingthe flow of lubricant from the bore portion 230 into the axial bore 60of the shaft 460.

The joint is supplied with lubricant and the arrangement is such that,during operation of the joint, the lubricant is forced to flow throughthe series of passageways ensuring continuous lubrication of the tracksalong which the balls are arranged to move.

The spring damping arrangement in FIG. 4 functions in precisely the sameway as the spring damping arrangement of FIG. 1.

FIG. 5 is highly diagrammatic representation of a shaft I9 connecting apair of joints each constructed as shown in FIG. 1, FIG. 2, FIG. 3, orFIG. 4 with the inner and outer members 10 and [2 thereof arranged foraxial movement and with spring means arranged to damp movement of theshaft 19 relative to the two outer members I0.

If the spring 38 is omitted from the joint of FIG. I, the head portion35 of the fixed guide element 34 will abut the shoulder provided at thejunction between the mouth portion 31 and the intermediate portion 32 ofthe bore 30 to limit the extent of travel of the inner member to theleft relative to the outer member as viewed in FIG. I.

If the springs 38a 38b, 38c respectively are omitted from the joints ofFIGS. 2, 3 and 4 respectively, the head portions of the guide elements34a, 34b, 34(' respectively will likewise act as travel limitingelements.

Ajoint as shown in any one of FIGS. 1 to 4 may be provided at one end ofthe shaft 19 with a joint as shown in specification No. 1,072,144 at theother end ofthe shaft.

We claim:

1. A plunging constant velocity joint which includes inner and outermembers formed with grooves, the grooves in the two members co-operatingto form tracks which are angularly distributed around the joint axis,torque-transmitting balls which are engaged in the tracks and move alongthem during relative movements between the inner and outer members, theinner member being formed with a bore, bearing means contained in saidbore and having internal part-spherical surface means the center ofcurvature of which coincides with the joint center. and a locationmember contained in said bore and having a part-spherical outer surfacecomplementary to and co-operating with, the internal surface means ofsaid bearing means, characterized in that the joint further includes anelongated guide element which is fixed relative to the outer member andis arranged with its longitudinal axis coincident with the longitudinalaxis of the outer member, and a helical spring surrounding saidelongated guide element and arranged to act between the location memberand the outer member to control relative movement between said members.

2. A plunging constant velocity joint according to claim 1 wherein thespring acts between a first abutment constituted by part of the locationmember and a second abutment which is fixed relative to the elongatedguide element.

3. A plunging constant velocity joint according to claim 1 wherein theelongated guide element, the location member and the inner member of thejoint are formed with lubricant passageways for the flow of lubricantsupplied from an external lubricant supply.

4. A plunging constant velocity joint which includes inner and outermembers formed with grooves, the grooves in the two members co-operatingto form tracks which are angularly distributed around the joint axis,torque-transmitting balls which are engaged in the tracks and move alongthem during relative movements between the inner and outer members, theinner member being formed with a bore, bearing means contained in saidbore and having internal part-spherical surface means the center ofcurvature of which coincides with the joint center, and a locationmember contained in said bore and having a part-spherical outer surfacecomplementary to and cooperating with, the internal surface means ofsaid bearing means, characterized in that the joint further includes anelongated element which is fixed relative to the outer member and passesthrough a bore in the location member, said elongated element beingprovided with an enlarged head portion arranged to co-operate with thelocation member to limit travel of the inner member relative to theouter member in one direction.

5. A plunging constant velocity joint according to claim 4 whereinresilient means are provided acting between the location member and theouter member to control relative movement between said members.

6. A constant velocity joint according to claim 5 wherein the resilientmeans includes a helical spring arranged with its longitudinal axiscoincident with the longitudinal axis of the joint outer member.

7. A constant velocity joint according to claim 4 wherein the elongatedelement, the location member and the inner member are formed withlubricant passageways for the flow of lubricant supplied from anexternal lubricant supply.

8. A constant velocity universal joint comprising an outer member havinga cylindrical bore formed with angularly spaced longitudinal grooves, aninner member having a partspherical outer surface formed with angularlyspaced longitudinal grooves each situated opposite a respective grooveof the outer member, torque transmitting balls each engaged in andbetween a respective pair of the opposed grooves, and a cage memberhaving openings in which the balls are received respectively, the cagehaving internal and external part-spherical guide surfaces whichrespectively engage the part-spherical outer surface of the inner memberand the cylindrical surface of the bore of the outer member to maintainthe balls in a bisector plane when the inner and outer members are displaced from an angularly aligned position, the centers of the guidesurfaces being spaced apart longitudinally so as to lie equidistantly onopposite sides of the center of the joint, characterized in that thejoint further includes a spring loaded location member fixed at one endto the outer member and having at the other end a part-spherical outersurface which has its center coincident with the center of the joint andcooperates with a complementary part-spherical surface internally of abore in the inner member of the joint, said location member actingdirectly between the outer member and the inner member.

l 4 t t i

1. A plunging constant velocity joint which includes inner and outer members formed with grooves, the grooves in the two members co-operating to form tracks which are angularly distributed around the joint axis, torque-transmitting balls which are engaged in the tracks and move along them during relative movements between the inner and outer members, the inner member being formed with a bore, bearing means contained in said bore and having internal part-spherical surface means the center of curvature of which coincides with the joint center, and a location member contained in said bore and having a partspherical outer surface complementary to and co-operating with, the internal surface means of said bearing means, characterized in that the joint further includes an elongated guide element which is fixed relative to the outer member and is arranged with its longitudinal axis coincident with the longitudinal axis of the outer member, and a helical spring surrounding said elongated guide element and arranged to act between the location member and the outer member to control relative movement between said members.
 2. A plunging constant velocity joint according to claim 1 wherein the spring acts between a first abutment constituted by part of the location member and a second abutment which is fixed relative to the elongated guide element.
 3. A plunging constant velocity joint according to claim 1 wherein the elongated guide element, the location member and the inner member of the joint are formed with lubricant passageways for the flow of lubricant supplied from an external lubricant supply.
 4. A plunging constant velocity joint which includes inner and outer members formed with grooves, the grooves in the two members co-operating to form tracks which are angularly distributed around the joint axis, torque-transmitting balls which are engaged in the tracks and move along them during relative movements between the inner and outer members, the inner member being formed with a bore, bearing means contained in said bore and having internal part-spherical surface means the center of curvature of which coincides with the joint center, and a location member contained in said bore and having a part-spherical outer surface complementary to and co-operating with, the internal surface means of said bearing means, characterized in that the joint further includes an elongated element which is fixed relative to the outer member and passes through a bore in the location member, said elongated element being provided with an enlarged head portion arranged to co-operate with the location member to limit travel of the inner member relative to the outer member in one direction.
 5. A plunging constant velocity joint according to claim 4 wherein resilient means are provided acting between the location member and the outer member to control relative movement between said members.
 6. A constant velocity joint according to claim 5 wherein the resilient means includes a helical spring arranged with its longitudinal axis coincident with the longitudinal axis of the joint outer member.
 7. A constant velocity joint according to claim 4 wherein the elongated element, the location member and the inner member are formed with lubricant passageways for the flow of lubricant supplied from an external lubricant supply.
 8. A constant velocity universal joint comprising an outer member having a cylindrical bore formed with angularly spaced longitudinal grooves, an inner member having a part-spherical outer surface formed with angularly spaced longitudinal grooves each situated opposite a respective groove of the outer member, torque transmitting balls each engaged in and between a respective pair of the opposed grooves, and a cage member having openings in which the balls are received respectively, the cage having internal and external part-spherical guide surfaces which respectively engage the part-spherical outer surface of the inner member and the cylindrical surface of the bore of the outer member to maintain the balls in a bisector plane when the inner and outer members are displaced from an angularly aligned position, the centers of the guide surfaces being spaced apart longitudinally so as to lie equidistantly on opposite sides of the center of the joint, characterized in that the joint further includes a spring loaded location member fixed at one end to the outer member and having at the other end a part-spherical outer surface which has its center coincident with the center of the joint and co-operates with a complementary part-spherical surface internally of a bore in the inner member of the joint, said location member acting directly between the outer member and the inner member. 